Submission #365068

#	Time	Username	Problem	Language	Result	Execution time	Memory
365068		saleh	Split the sequence (APIO14_sequence)	C++17	71 / 100	2076 ms	9452 KiB

sequence

#pragma GCC optimize("Ofast")

#include <bits/stdc++.h>

#define int long long

using namespace std;


const int MAXN = 100 * 1000 + 2, MAXK = 200 + 2;
















int n, k, dp[2 + 2][MAXN], ps[MAXN], a[MAXN], chi;
int32_t par[MAXK][MAXN];

void cal(int lvl, int l, int r = n + 1, int ll = chi, int rr = n) {
	int mid = ((l + r) >> 1), md = -1;
	dp[lvl][mid] = -1;
	for (int i = ll; i < mid && i < r; i++) {
		if (dp[1 - lvl][i] + ps[i] * (ps[mid] - ps[i]) > dp[lvl][mid]) {
			dp[lvl][mid] = dp[1 - lvl][i] + ps[i] * (ps[mid] - ps[i]);
			md = i;
		}
	}
	par[chi][mid] = md;
	if (l < mid) cal(lvl, l, mid, ll, md);
	if (mid + 1 < r) cal(lvl, mid + 1, r, md, rr);
}



int32_t main() {
	ios_base::sync_with_stdio(false);
	cin.tie(nullptr), cout.tie(nullptr);
	cin >> n >> k;
	for (int i = 0; i < n; i++) {
		cin >> a[i];
		ps[i + 1] = ps[i] + a[i];
	}
	for (int i = 1; i <= k; i++) {
		chi = i;
		cal(i & 1, i);
	}
	cout << dp[k & 1][n] << '\n';
	while (k > 0) {
		cout << par[k][n] << ' ';
		n = par[k][n];
		k--;
	}
	return 0;
}

• Subtask 1: 11 / 11
• Subtask 2: 11 / 11
• Subtask 3: 11 / 11
• Subtask 4: 17 / 17
• Subtask 5: 21 / 21
• Subtask 6: 0 / 29